People's interest in security is increasing every year. For example, attracting high attention is detection of wandering of patients with dementia, prevention of infant abduction, etc. (hereinafter, summarily referred to as “safety management.” Further, a safety management action refers to an action taken in relation to the safety management). As a system for performing such a safety management action, there is known a safety management system that includes a wandering sensor(s) as a main component thereof. In this safety management system, entering of a person carrying a transmitter tag into a predetermined zone in a hospital, for example, is detected by a receiver, which transmits the ID information and the like stored in the transmitter tag to a management device, thereby notifying wandering behaviors in real-time.
As another example of such a system, disclosed is a safety management system in which transmitters are fitted on children (namely, those who need supervision), and presence of a child or children in predetermined areas of a facility is detected by multiple antennas, such that the locations of the children can be recognized based on the detection information from the antennas, and the number of the detected children and their degree of risk are assessed by a wireless communication server (see JP2004-118362A).
Further, as technology relating to the aforementioned safety management, disclosed is a security monitoring system in which, to detect theft of a terminal device such as a notebook PC (namely, absence of the terminal device where it should be), the terminal device is configured to, upon activation, obtain longitude and latitude from the GPS (Global Positioning System), and when the location indicated by the obtained longitude and latitude is outside an area in which the use of the terminal device is permitted, perform notification to the security monitoring center (see JP2007-102441A).
However, in the safety management system using wandering sensors, it is necessary to mount a number of sensors (receivers) at various locations in the hospital such as corridors and patient rooms, for example, in addition to installing a management device for collecting the outputs from the sensors and, in some cases, laying the lines to connect the management device to a central device operated by a company. Thus, the cost of laying the lines and installing the management device tends to increase the total cost of the system.
The technology disclosed in JP2004-118362A also requires a large-scale configuration including the multiple antennas and wireless communication server, and thus, tends to be so expensive that cannot be purchased easily by personal users.
The technology disclosed in JP2007-102441A uses the data communicated between the terminal device and the management device when the terminal device is connected to the network and the position information from the GPS or the like, and thus, the system also cannot be purchased easily by personal users.